Efficient oill shale recovery method

ABSTRACT

The subject matter herein provides a biotic method for recovering one or more hydrocarbons from a feedstock that includes one or more of oil shale, bituminous tar sand, coal and cellulous at atmospheric temperature and pressure. The method comprises loading the feedstock into a container, treating the feedstock in the container with a biomedium of micro-organisms, and forming an essentially liquid mixture from the feedstock and the biomass by rotary tumbling the feedstock and the biomedium in the container. The essentially liquid mixture is then separated into the one or more hydrocarbons by centrifuging.

RELATED APPLICATION

This divisional application claims priority benefit of co-owned,co-pending CIP application Ser. No. 14/829,215 (filed on Aug. 18, 2015)to be issued as U.S. Pat. No. 9,550,943 on Jan. 24, 2017, which claimspriority benefit of co-owned, co-pending U.S. Provisional PatentApplication No. 62/165,103 filed on May 21, 2015; and, of co-owned,co-pending non-provisional patent application Ser. No. 13/338,883 filedon Dec. 28, 2011, which claims priority benefit of U.S. ProvisionalApplication No. 61/552,115 filed on Oct. 27, 2011 all of which areincorporated herein in their entireties by reference.

TECHNICAL FIELD

The inventive process described herein is in the field of obtaininghydrocarbons, minerals and elements from oil shale, tar sand and coal;and, obtaining hydrocarbons from cellulose material. More specifically,the process is conducted at atmospheric temperature and pressure withthe use of microorganisms.

BACKGROUND

Large quantities of hydrocarbons are trapped in geologic formationsaround the world. Crude oil and natural gas are the only hydrocarbonsthat naturally occur. These are viewed as strategic resources because oftechnological dependency on petroleum products for fuel and rawmaterials. Coal is a significant source of hydrocarbons for energyproduction and manufacturing.

Crude oil, natural gas, and coal are the most widely utilized sources ofhydrocarbons because they are relatively inexpensive to find and refine.Thus, every spike in the price of common hydrocarbons stimulatesinterest in alternative sources of hydrocarbons.

Oil shale is such an alternative source. Oil shale is a hydrocarbonsource rock composed of inorganic sedimentary particles and appreciableorganic material. Some estimates suggest that global deposits of oilshale contain roughly three trillion barrels of recoverablehydrocarbons. Kerogen, the organic material in oil shale, is the solidprecursor to crude oil, natural gas, and coal. Over geologic time,kerogen deep in the Earth decomposes under geothermal pressure andtransforms into petroleum products.

This geologic process can be mimicked by retorting. Retorting is amethod of extracting recoverable hydrocarbons that involves heating oilshale to several hundred degrees centigrade in the absence of oxygen.The kerogen in the oil shale decomposes into numerous hydrocarbon richgases that are collected and liquefied. The liquefied “shale oil” isthen refined and processed similarly to crude oil.

Unfortunately, many oil shale deposits contain as little as 25% kerogen.Further, there is a significant energy loss associated with heating theinert geologic materials in the oil shale to several hundred degreescentigrade. Thus, producing shale oil is not economically viable inregard to it's “energy return on energy invested” (EROEI), unless theprice of crude oil is greater than about $75 a barrel. Retorting on alarge scale is not desirable because of potential environmentalpollution and heavy demand upon water resources. The environmentalpollution is exacerbated because potentially valuable inorganicmaterials and metals are not recovered from the spent shale andadvantageously disposed of.

The EROEI of oil shale can be improved by enriching the kerogen contentprior to retorting. This enrichment is very problematic because kerogenis insoluble and impervious to organic solvents. One solution is tocrush the oil shale in order to expose more kerogen during retorting.Other solutions include using acid treatments to reduce the amount ofrock in a sample of shale.

Limited biotic decomposition of kerogen is possible (See, e.g., U.S.Pat. No. 2,641,565) but its use has apparently been economicallyunsuccessful, which is evidenced by its lack of pervasive commercial useover the last 100 years. There are known species of bacteria that areable to consume kerogen, but the bacteria excrete unknown compounds. Onthe other hand, while some bacteria have been genetically modifiedbacteria to excrete hydrocarbons, these do not consume kerogen.

Although producing hydrocarbons through biotic decomposition has not yetproven economically successful, there has been limited success inprocessing oil shale with microorganisms. For instance, the ability ofcertain bacteria to excrete acid has been applied to dissolve theinorganic sedimentary matrix in oil shale (See, U.S. Pat. No.3,982,995). That inventive method produces sponge-like shale withincreased surface area to promote combustion of the kerogen.

Coal, which is a solid derivative of kerogen, can be processed similarlyto oil shale in order to obtain liquid and gaseous hydrocarbons. Allmethods of coal liquefaction and gasification require significantheating of the coal. This leads to the same problems experienced as withshale oil including low EROEI and extensive environmental pollution.

There are two methods of coal liquefaction, direct liquefaction (DCL)and indirect liquefaction (ICL). The DCL process is operated between302-572° F. (150-300° C.) and at a pressure range between one andseveral tens of atmospheres. Higher pressures would be favorable, butthe benefits may not justify the additional cost of high-pressureequipment. The DCL process, like retorting used in oil shale, firstcoverts the coal to a gas, then condenses it to a liquid. The ICLprocess avoids the gasification process by using solvents or catalystsin a high pressure and high temperature process.

Cellulose (C₆H₁₀O₅) does not contain hydrocarbons but is instead acarbohydrate. Hydrocarbons and carbohydrates are not interchangeable andcannot be conflated. However, microorganisms such as yeast can convertcellulose and water into liquid hydrocarbons through fermentation.Agricultural waste and recycled wood are common sources of cellulose forsuch purposes. As with methods of hydrocarbon recovery, manufacture ofhydrocarbons from cellulose has significant drawbacks including lowEROEI and extensive environmental pollution.

Conversion of a cellulose biomass into biofuel is currently achieved bythermal conversion. The major methods of thermal conversion arecombustion in excess air, gasification in reduced air and pyrolysis inthe absence of air. A number of combustion technologies are available,all requiring boilers or fluid bed combustors. The latter can producefuels with lower NOx levels. Co-Firing, using a fossil fuel is also usedas a combustion method. Gasification produces a lower calorific valuebut can still be used as a fuel for boilers, engines, and possiblycombustion turbines but requires cleaning the gas stream of tars andparticulates. Pyrolysis is thermal degradation in the absence of air. Itproduces a solid char, gas and a liquid bio-oil. The bio-oil can act asa liquid fuel.

A common thread among the efforts to obtain hydrocarbon fuels from oilshale, coal, tar sands, and cellulose has been the excessive cost. Weknow the cost to produce a barrel of kerogen using ex situ retortingmethods is between $156 and $200 a barrel. With crude oil selling on theworld markets between $40 and $75 a barrel, the cost to produce a barrelof kerogen hydrocarbon has a negative EROEI. No matter how efficientcurrent in situ or ex situ retorting methods are, producing a barrel ofhydrocarbon(s) using known methods is cost prohibitive. Each of oilshale, coal, tar sands and cellulose requires heating the feedstock tohundreds of degrees. In addition, the condensation of hydrocarbon gasesfrom oil shale, coal and tar sands to a liquid form is an expensiveprocess. What is needed is a method to produce hydrocarbon fuels fromthese various feedstocks with a lower EROEI than gasoline.

SUMMARY OF THE INVENTION

A method for recovering one or more hydrocarbons from a feedstock thatincludes one or more of oil shale, bituminous tar sand, coal andcellulous is provided. The method comprises loading the feedstock into acontainer, treating the feedstock in the container with a biomedium ofmicroorganisms, and forming an essentially liquid mixture from thefeedstock and the biomass by rotary mixing the feedstock and thebiomedium in the container. The essentially liquid mixture is thenseparated into the one or more hydrocarbons, water, the biomedium andresidual inorganic material.

A method for recovering one or more hydrocarbons from a feedstock thatincludes one or more of oil shale, bituminous tar sand, coal andcellulous is provided. The method comprises loading the feedstock into aBiodigester, treating the feedstock in the Biodigester with a biomediumconsisting essentially of slime mold, and forming an essentially liquidmixture from the biomass by rotary mixing the feedstock and thebiomedium in the Biodigester. The one or more hydrocarbons are separatedfrom the essentially liquid mixture by centrifuging.

A method for recovering one or more hydrocarbons from a feedstock thatincludes one or more of oil shale, bituminous tar sand, coal andcellulous is provided. The method comprises loading the feedstock into aBiodigester, treating the feedstock in the Biodigester with a biomediumcomprising slime mold, and forming a liquefied mixture from thefeedstock and the biomedium by mechanically mixing the feedstock andmetabolizing the feedstock by the biomedium in the Biodigester. Themethod further comprises separating the essentially liquid mixture intothe one or more hydrocarbons

BRIEF DESCRIPTION OF THE DRAWINGS

These and other features, aspects, and advantages of the presentdisclosure will become better understood with regard to the followingdescription, appended claims and accompanying drawings, where:

FIG. 1 is a flowchart of an exemplary method(s) described herein;

FIG. 2 illustrates an exemplary, non-limiting embodiment of aBiodigester used in the methods described herein; and

FIG. 3 illustrates an exemplary, non-limiting embodiment of an air-tightlid subsystem for the Biodigester of FIG. 2.

DETAILED DESCRIPTION AND EXEMPLARY EMBODIMENTS

The subject matter herein presents a method 100 for recoveringhydrocarbons from oil shale using microorganisms in a biomedium atatmospheric temperature and pressure (e.g., room temperature). This isadvantageous over prior methods like retorting because it is costeffective. Unless being done in a frigid environment, there is no needto heat the oil shale, thereby making the inventive method 100 lessexpensive than other methods of shale oil extraction. Further, waste andpollution are reduced. This method 100 is adaptable to recoverhydrocarbons from coal, tar sand, and cellulose materials.

In method 100, a load of oil shale, coal, tar sand and/or cellulose(i.e., feedstock) is treated with a biomedium containing microorganisms,water, muriatic acid and nutrients and then mechanically agitated.During the process, the microorganisms recover hydrocarbons from the oilshale, coal, tar sand, and/or cellulose by metabolic action. After asuitable period of mechanical agitation, a liquid or colloidalsuspension comprising biomedium, one or more hydrocarbons, and inertmaterials is produced. The components of the liquid suspension areoptionally purified by centrifuge, decanting, filtration, cleaning,and/or washing.

The EROEI of this method 100 is significantly lower than previousmethods for hydrocarbon recovery. The biomedium can be recycled and usedagain. Furthermore, the inert materials in the liquid are potentiallyvaluable metals, minerals, elements, and compounds that can more easilybe processed into useful commodities. Such materials have not beenrecovered with other prior art processes.

The method 100 is environmentally friendly for three reasons. First, themethod 100 avoids the unnecessary energy expenditures associated withheating inert materials. Second, it uses a biomedium comprisingnaturally occurring, nonpathogenic microorganisms rather than harshchemicals. Third, the biomedium can be recycled and reused. Lab testssuggest the components of the gases released during method 100 arenitrogen, oxygen, argon, carbon dioxide, neon, methane, and helium inamounts that are substantially similar to the composition of air. Anyinert materials from which no valuable metals, minerals, elements, orcompounds can be extracted are sold or are returned to the mining siteto rehabilitate the land.

Microorganisms are used to recover hydrocarbons in oil shale, tar sand,and coal. The microorganisms potentially can also produce hydrocarbonsfrom any cellulose material. In one embodiment, the microorganisms aretaught or induced to recover hydrocarbons by lightly sealing themicroorganisms, water, and nutrients with a model source of hydrocarbonssuch as oil shale, tar sand, cellulose and/or coal. After twenty onedays, a biomedium containing the microorganisms develops that canrecover the hydrocarbons trapped in the source of hydrocarbons.

The addition of muriatic acid provided the best test results. Thus,microorganisms that could thrive in an acidic environment have been mosteffective. In the embodiments described herein Orange Mold was usedbecause of the acidic nature of its food source.

Orange Mold is a particular type of Slime Mold that consumes citrusfruit. It is harmless to humans. While it is primarily orange in color,this unique mold can sometimes also appear to be red or pink. Orangemold is found on decaying organic matter and survives off of bothbacteria and fungi, as well as other tiny organisms not be visible tothe naked eye.

Slime molds are single celled organisms that were once classified in thedefunct kingdom Protista and subkingdom Gymnomycota and included thedefunct phyla Myxomycota, Acrasiomycota and Labyrinthulomycota. Today,slime molds have been divided between several supergroups, none of whichis included in the kingdom Fungi. Slime molds comprise the Mycetozoangroup of the Amoebozoa. Mycetozoa include Myxogastria (plasmordial slimemolds), Dyctyosteliida (cellular slime molds), and Protosteloids (amoebathat create spores).

Slime Molds obtained from a variety of decaying organic matter have beentested and they all are effective. However, Slime Mold from decayingacidic fruits produces the best results.

In addition to Slime Mold, moldy acidic citrus fruits may also containbacteria and fungus such as Penicillium digitatum (a fungus called“green mold”), Penicillium italicum (fungus called “blue and green fruitmolds”), Mycosphaerella citri (fungus), Pseudomonas syringe (bacteriumexisting in over 50 different pathovars), Xanthomonas axonopodis(bacterium); Aspergillus niger (fungus), Alternaria citri (fungus),Phytophthora citricola (fungus), Phytophthora citrophthora (Fungus),Phytophthora hibernates (fungus), Phytophthora nicotine (fungus),Phytophthora syringe (fungus); Ashbya gossypii (fungus closely relatedto yeast), Nematospora corylicauses, (fungus), Fusarium (fungus),Botryyis cinerea (fungus), Mucor paraonychius (fungus), Mucor racemosus(fungus), Eisinoe australis (fungus) and/or combinations thereof. Alongwith the slime mold, these are the known molds, fungus and bacteriumthat are found along with “Orange Mold”. Hence, a Slime Mold is used inconjunction with a combination of molds, fungi, and bacteria. It shouldbe noted that Slime Molds consume bacteria and fungus. Hence, fungi andbacteria are apparently a food source for the Slime Mold in thebiomendium and are not necessarily the primary microorganism acting onhydrocarbons although some may, such as those disclosed in U.S. Pat. No.2,641,565.

Various Slime Molds obtained from the decay of various acidic fruits orvegetables were investigated. Further, the natural pH levels of thevarious fruits and vegetables was determined. Each fruit or vegetabletested as a slime mold source for liquefying oil shale, coal, tar sands,and cellulose is listed below along with its pH level. All sources ofSlime Mold work to one degree or another, but the best results wereobtained from those fruits or vegetables with a natural pH at or below3.5. The bold, capitalized entries below in Table 1 produced the bestexperimental results:

TABLE 1 Fruit/Vegetable pH Fruit/Vegetable pH Fruit/Vegetable pHFruit/Vegetable pH APPLE 3.3 Kumquat 3.6 PINEAPPLE 3.2 Raisins 3.8BLUEBERRIES 3.1 LEMON 2.0 Plum 2.8 Red Pepper 3.1 Crabapple 2.9 LIME 2.0Pomegranate 2.93 Rhubarb 3.1 Cranberry 2.3 Mayhaw 3.27 Peaches 3.28Sauerkraut 3.3 Gooseberries 2.8 Mint 3.0 Pears 3.5 Strawberries 3.0GRAPES 2.8 Mustard 3.0 Prunes 2.0 Tangerine 3.32 GRAPEFRUIT 2.0 Olives3.6 Potato 3.63 TOMATOES 3.5 Guava 3.7 ORANGES 3.3 Rasberries 2.87Vinegar 2.4 Yangsberries 3.0The most commonly available produce were the citrus fruits, pineapple,potato and tomato. All except potatoes gave satisfactory results whenliquefying oil shale, coal, tar sands and cellulose. The best performingSlime Mold came from a mix of citrus fruits and tomatoes. Adding onionsproduced good results. When using moldy peppers, watermelon orcantaloupe the results either failed or were unsatisfactory. Hence,Slime Mold per se is not necessarily effective. Cultivation or“training” is required.

Laboratory tests performed by the Applicant have shown that mostmicroorganisms found on or around plants can be used in method 100 withvarying degrees of success. Once selected, the microorganism(s) wereblended or whisked using a typical blender at process 110, to create thebiomedium. In a commercial scale operation larger industrial mixers areused. There is often sufficient water inherent in the medium for thegrowth process to take place, however a small amount of water may beadded to help liquefy the Slime Mold cultures.

To the newly liquefied Slime Mold cultures, a food, nutrient or otheraccelerant source is added, such as sugar, molasses, yeast and a quickrelease aqueous, nontoxic, nonhazardous environmentally safe surfactantto form a biomass or biomedium. The biomasss is then mixed again. Thefood (i.e., molasses, sugar) may be food for the yeast/fungi/bacterium,which are in turn food for the Slime Mold. While it is believed any“quick release” non-hazardous, nontoxic and environmentally safesurfactant will work. Such surfactants are generally available fromspecialty chemical manufacturers, distributors and dealers around theUnited States. The use of a surfactant may shorten the time required forthe liquefaction of the oil shale, hydrocarbons from coal, tar sands orcellulose material. The 12-hour time frame disclosed herein was donewithout the use of any surfactants, and with them the timeframe may beshorter.

Sugars.

Different kinds of sugar were investigated. All the white sugars,including bakers special sugar, barbados sugar, confectioner's sugar,powdered sugar, coarse sugar, date sugar, fruit sugar, granulated sugar,raw sugar, sanding sugar, superfine, ultra-fine (or bar sugar), and evensugar cubes (made from moist granulated sugar), brown sugars, includinglight and dark brown sugar, demerara sugar, muscovado sugar, freeflowing brown sugars, turbinado sugar, and even some of the liquidsugars such as liquid sugar and invert sugar were used to varyingdegrees of success. The best results were obtained using naturalgranulated pure cane sugar.

Molasses.

A variety of molasses, from fancy molasses, lite molasses, cookingmolasses, unsulphured molasses, and blackstrap molasses wereinvestigated. As with the sugars, the type of molasses is not easilyidentifiable on the package. The best results have been obtained usingblackstrap molasses.

Yeast.

There are at least 1,500 species currently identified. Of the myriadtypes of yeasts reasonably obtainable, the best result s were obtainedfrom yeasts simply labeled “active dry yeast.”

Process 110 of method 100 varies depending on the feedstock to beliquefied, oil shale, coal, tar sands, cellulose material and/or aspecific combination thereof. However, the process 110 is the basicallysame except for material.

At this point, the ratios for a small biomass volume used to “train” themicroorganisms will be described. About three cups of oil shale, coal,tar sand, and/or cellulose material was added to a glass container andstirred. About 1.5 teaspoons (0.5 fluid ounces) of muriatic acid wasadded, and then the combination was agitated by stirring or whisking.The acid added is the same strength as found for swimming pool use,which is relatively safe. Trials with and without the addition ofmuriatic acid were conducted. While the result was the same, the entireblend seems to react better and work faster when the acid was added. Wehave found the same results using either plastic or steel containers.The order of the steps in process 110 were varied with successfulresults. However, the preceding description of steps gave the mostaggressive results. One or more constituents were selectively omitted.However, these abridged methods produced inferior results.

After thorough mixing, the container was lightly sealed (not too tightas the action of the microorganisms will generate a positive pressurefrom a small amount of gas production). If the lid is too tight, onerisks the container or lid breaking.

Process 120 is the “training” or “incubation” of the desired biomedium.After collecting preparing the moldy fruits and vegetables to use, theSlime Mold, other molds, fungus, and bacteria combination required toprocess a specific feedstock as a food source was required. Trainingmicrobes is accomplished by slowly introducing the feedstock one wishesto process, in this case being oil shale, coal, tar sands and/orcellulose. While the training process 120 is underway, nutrients areadded, the pH of the resulting biomass is adjusted/maintained belowapproximately 5.5 pH, and the biomass is be stirred or whisked so thatit becomes a uniform and homogeneous blend. Within twenty minutes aftercreating the homogeneous biomass, if bubbles form on the feedstock it isan indicator of success.

The biomass and feedstock mixture was subsequently stored in a darkplace for at least 30 minutes before checking training progress. Signsof progress include small bubbles forming throughout the mix, whichmeans that the mixture is working with the feedstock. This is a positivesign, but it is not necessarily bad if there are no bubbles, which maytake longer to form. The container was then placed back in a dark placewhere the temperature is between 50° F. (10° C.) and no higher than 100°F. (37.8° C.).

A preferred storage time was as much as 21 days before use, but lesstime also worked. Basically the longer the incubation time (up to the 21days), the greater is the eventual yield from the blend. During thisperiod, the Slime Mold and other microorganisms are adapting as acontained ecosystem to use portions of the feedstock ultimately causingthe feedstock to liquefy.

Training times in excess of the 21 days have not been tested. However,the trained biomass has been stored for as much as 6 months to a year(in one case well over a year). The microorganisms simply seemed toeventually go dormant, and no more bubbles were created.

Larger quantities of microorganisms have been tested. The previouslydescribed biomass was about 8 cups (64 fluid ounces) in volume. To growthe microorganism mixture by 400%, four one gallon jars were used. Twocups (16 fluid ounces) of the original biomass were placed into eachjar. The amounts were not exact.

At process 130, a larger batch was created and grown to a desired sizestarting with one cup (8 ounces) of warm water along with fourmedium-size moldy oranges and blended it until it was a homogeneousfluid. The volume of this was about 4 cups (32 fluid ounces). This newmicroorganism mix was equally divided into four gallon jars.

Three cups (24 fluid ounces) of warm water were added to each jar. Next,one tablespoon (0.5 fluid ounce) of molasses was added, 0.5 teaspoon(0.083 fluid ounce) of sugar was sprinkled on top of the mixture, and 1teaspoon (0.17 fluid ounces) of yeast was also sprinkled on top. Thismixture was stirred or whisked until the nutrients were blended.

One teaspoon (0.17 fluid ounce) of muriatic acid was added to 0.5 cup ofwarm water, whereby the concentration was similar to that of swimmingpool water. The diluted acid was then added it to each jar and againstirred or whisked until blended.

The addition of the ingredients in the order above is the preferredprocess. However, variations in the order were tested and while the endresults are the same, the order above seems to give the most effectiveresult. Ordered steps leaving one or more of the ingredients out andvarying the quantity of the ingredients were tested with varyingresults.

Although it may not be necessary, ⅓ cup (2.67 fluid ounces) ofadditional oil shale, coal, or cellulose material (whatever we wished toliquefy) was routinely added incrementally. However, we believe thisaddition may be unnecessary.

This larger batch size grew the original volume of microorganism mix toabout 96 ounces of biomedium in each jar. It is believed that one cangrow the biomedium to larger volumes simply by scaling the proportionsto fit the volume.

The biomass was stored in a dark area where the temperatures arecomfortable for humans. The required number of days of storage hereseemed to be much shorter, roughly 3-4 days. It could be stored longerwith no decrease in effectiveness. The 96-ounce microorganism mixture isabout the smallest amount needed for commercial liquefaction of oilshale, coal or cellulose material and that is the next process.

Larger quantities will be needed for some commercial processes. Aconcrete mixer may be used to rotate and/or agitate thebiomass/feedstock mix without spilling. For example, smaller scalecommercial rock tumblers usually are built to optionally seal thetumbler watertight, but concrete mixers do not. If the container is notsealed, there may be off gassing of methane, but the amount is small.Optionally, a tumbling medium is placed into the rotary tumbler toreduce the oil shale rock size faster. Tumbling medium includes ceramicfigures, metal shot, abrasive particles, as well as any other mediumnormally used by a person of ordinary skill in the art.

However, in larger amounts a simple tumbler does not offer the properamount of agitation to the mix and fails to liquidate the oil shale,coal, tar sands, or cellulose fully. What is more effective is a mixer,similar to a rotary concrete mixer on an inclined plane. A horizontalmixer works as well, but must have fins or blades to be able to pick uppart of the biomass and dump it back into the main biomass. Hereinafter,I will refer to the converted mixing device as a “Biodigester.”

As Biodigesters, commercial mixers, even large concrete mixers may bemodified to control any off-gassing using a sealed door system. Anexemplary Biodigester is described more fully in co-pending, co-ownedU.S. Provisional Application No. 62/165,103.

A Biodigester as described herein may be distinguished from a “tumbler.”Tumblers, are generally recognized by those of ordinary skill in the artas being a round or hexagonal drum that when rotated simply force themixture up the inside of the drum to a small height. When gravityovercomes centrifugal force imparted by the tumbler, the mass slidesdown the side and begins the process again. To the contrary, the termBiodigester as used herein refers to a modified “mixer,” similar to arotary concrete mixer mounted on an inclined plane with internalcircumferentially mounted mixing vanes. A non-limiting example of anunmodified inclined rotary mixer is discussed in detail in U.S. PatentPublication 2008/0291771 to Khouri, which is included herein byreference in its entirety. A non-limiting example of an unmodifiedrotary mixer with axially mounted mixing vanes is discussed in moredetail in U.S. Patent Publication 2004/0179423 to Asami, which isincluded herein by reference in its entirety.

Mixers of size, even concrete mixers, my not execute the process unlessthey are modified to be able to control any off gassing. The subjectmatter disclosed herein includes an airtight sealed lid system that maybe used on a conventional concrete mixer up to a size of 20 cubic yardsor more.

Another functional consideration is whether or might not the internalsurface of the mixing drum of the Biodigester is lined to preventchemical damage to the drum, or if it is comprised of stainless orregular steel. No lining and the use of regular steel apparently worksbest. The chemicals used in liners or coating inside a conventionalmixer may degrade causing a failure of the biomass to liquefy the oilshale, coal, tar sands, and/or cellulose. However, there may be someliner material that would not interfere with the biomass.

FIG. 2 is an exemplary, non-limiting example of a Biodigester 10 that issuitable for bio-mechanical methods used in recovering one or moreliquid hydrocarbons from one of oil shale, tar sand, coal and/orcellulose as more fully described in U.S. Provisional Patent No.62/165,115 to Wallage that is incorporated herein in its entirety.

Generally, as a non-limiting example, the Biodigester 10 comprises amixing drum 30 with a first axial end 40 and an opposite axial end 42with a radial opening 38 at the first axial end 40. The mixing drum 30has an inner surface 58 and an outer surface 60. The Biodigester 10 isrotated bi-directionally by a motor (not shown) engaging a drive ring 34and is rotatively supported in a frame (not shown) by roller ring 36.

The Biodigester 10 contains spiral mixing vanes 32 fastened to theinside surface 58 of the mixing drum 30 that agitate the biomass duringthe hydrocarbon recovery process. Rotating the mixing drum 30 in onedirection drives the biomass into the opposite axial end 42 and keeps itagitated. Rotating the mixing drum 30 in the opposite direction movesthe biomass out of opening 38.

Alternatively, the spiral mixing vanes 32 may instead be straight mixingvanes 32 attached to the inside surface 58 of the mixing drum 30 andoriented parallel to the rotational axis of the mixing drum 30. As themixing drum 30 turns, the mixing vanes 32 pick up a portion of thebiomass and drop it from a height back into the bottom of the mixingdrum 30, thereby fully agitating and aerating the biomass containedtherein (not shown).

The opening 38 includes a removable lid 70 to facilitate the capture andcontrollable release of by-product gasses produced during processing ofthe feedstock by the biomass. FIG. 3 illustrates an exemplary,non-limiting lid subsystem for the Biodigester 10 of FIG. 2. The lid 70is attached to a lever arm 72 which allows its placement and removal.The lever arm 72 is connected to the lid 70 by a rotating joint member80. The rotating joint member 80 may be any suitable device known in theart that will allow rotational freedom between the stationary level arm72 and the lid 70, which rotates with the mixing drum 30. Rotating jointmember 80 may range from a simple axel pin, to a ball joint, to anarticulated, multi-axial device.

The removable cover 70 abuts the opening 38 via one or two elastomeric(e.g., neoprene) gaskets 76 that are sandwiched between the opening 38of the mixing drum 30. The use of two neoprene gaskets 76 allows the lidto be fitted air tight to the opening 38 and facilitates the retentionof gasses produced during the biomass processing. One neoprene (i.e.,rubber) gasket 76 may be attached to each of the opening 38 and the lid70. Fitting/valve 81 penetrates lid 70 and is used to vent or bleed offpressure inside the mixing drum 30 due to the buildup of gasses in themixing drum 30. Fitting/valve 81 may be an automatic relief valve or amanually controlled valve that controls gas flow into a takeoff hose(not shown) that may be attached thereto for venting or for gas capture.

The lever arm 72 is rigidly attached to hinge bar 78, which is supportedby static frame 73. Hinge bar 78 is attached to and operated by leverarm 77 which is in turn operated by piston 74. Piston 74 extends to openthe lid 70 by moving lever arm 77 through hinge 79. It must bereiterated that the described lid system is merely exemplary and othermechanical control mechanisms may be applied to manipulate the air-tightlid 70 and to control degassing.

As an alternative non-limiting equivalent embodiment, the frame 73 maybe attached only to the mixing drum 30 and not be attached to a staticframe or the ground. As such, the entire frame 73 for securing theairtight lid 70 may rotate with the mixing drum 30, thereby obviatingthe need for rotating joint member 80.

22-Gallon Batch Directions. A small mixer capable of holding about 22pounds (about 10 kilograms) of oil shale, coal or cellulose material wasneeded. A tumbler with a capacity of about 25-30 gallons was used as amatter of convenience. After breaking feedstock into pebble-size pieces,the feedstock was loaded into the Biodigester (See, FIG. 1, process140). These smaller pieces provide greater surface area for themicroorganism blend to contact and increase the efficiency of theprocess. Enough water was include to cover the feedstock. Warm (not hot)water will speed up the process. Potable water, or virtually any wateris satisfactory as long as it does not contain contaminants that willkill the microorganism mixture.

The biomedium mixture was poured into three (3) one-quart (96 ounces)containers. If there is less, liquefying the feedstock material willtake longer. More mixture may speed up the process, but sincemicroorganism mixtures are relatively expensive, the amounts discussedherein may be the optimum amount for commercial profitability.

At process 150, about three cups of yeast were scattered evenly over thesurface of the feedstock/biomass mixture and about one half cup of sugar(see discussion above) was added. The door on the tumbler or mixer, ifit has one, is closed and preferably sealed air-tight. The small mixerused in testing had a bolt-on cover. There are variances in the type ofseal that may be used that will not affect the outcome.

At process 160, the Biodigester is turned on to rotate and agitate theentire mixture by mixing. The mixing speed may affect the speed at whichthe microorganisms will liquefy the contents. This method has hadsuccess in liquefying oil shale in less than 12 hours. Faster speeds mayspeed up the process. Slower speeds may slow the process. Processingusing the upper speed limits on the Biodigester have not beeninvestigated, however, the speed must be limited to one that does notcause the biomass/oil shale mix to rotate with the mixer during themixing process due to centrifugal force.

As a non-limiting example using a 12 ton load of feedstock, enough wateris added to completely cover the load. For best results, the feedstockwas crushed to a “pebble.” A pebble is a specific term used for a sizeof ore, and is a particle size of 4 to 64 millimeters (0.157-2.5 inches)based on the Krumbein scale of sedimentology. All ex situ methods knownto treat oil shale, using microorganisms or not, crush the ore to a“fine” particle size. A fine particle size is 125-250 mμ (millimicron)(0.0049-0.0010 inches) based on the same scale. For comparison, talcumpowder dust is 0.5-50 microns, so a “fine” is much smaller. Only havingto reduce the ore to a “pebble” is a significant cost savings for thisprocess.

The ideal amount of microorganism mix, yeast and sugar, as discussedbelow, are sufficient to free substantial amounts of one or morehydrocarbons from the load of feeds stock in about 24 hours. Twelve tonsequals 24,000 pounds of oil shale, coal, tar sand and/or cellulose.Twenty-four thousand (24,000) pounds is about 1,090 times 22 pounds.Three quarts of microorganism mixture equals 96 ounces. Ninety-sixounces multiplied by 1,090 equals 104,640 ounces. Hence about 817gallons of microorganism mixture would be needed. Three (3) cups ofyeast would equate to 3,270 cups of yeast or about 204 gallons of yeast.One half cup of sugar would equate to about 17 dry gallons of sugar. Ofcourse, one could use fewer microorganisms, yeast or sugar, and morewater, but it takes longer for the quantity of microorganisms to growinto the quantity necessary to liquefy the feedstock material.

In an alternative embodiment, the amount of biomass or biomedium can bescaled for different needs. The amounts of water, nutrients, feedstock,and muriatic acid may be increased or decreased so long as amounts ofeach ingredient are scaled equally. We have been able to store thebiomedium at approximately room temperature for as long as about twentyone days.

As the biomedium consumes the nutrients, the mixture of biomedium andoil shale may become progressively more acidic. The acid assists todissolve the matrix of the feedstock. Mechanical agitation promotesbreaking of the feedstock matrix and exposes increasing portions of thematrix to the biomedium and acid. The biomedium contains enoughmicroorganisms, water, and nutrients to produce a sufficient quantity ofSlime Mold, bacteria and fungi and the resulting acid for the durationof processing.

In yet another exemplary embodiment, the biomedium is placed in a smallrotary mixer with pea-size oil shale. The mixer mechanically agitatesthe mixture for approximately twelve hours to produce a liquid or acolloid suspension, depending on the feedstock composition. The durationof mechanical agitation varies at least with the particular type offeedstock, the degree of enrichment, and size of the feedstock load. Theend result of the disclosed method 100, infra, is a complete and totalconversion of the feedstock load from a solid to a liquid state, or acolloid suspension, but not a slurry.

A slurry is a watery mixture of insoluble matter (such as mud, lime orplaster of paris) (See, Webster's New Collegiate Dictionary, G&C MeriamCompany, Springfield Mass. (1973). A slurry is often used as aconvenient way of handling solids in bulk. Being in a slurry does notchange the state of the solids, but only makes them easier to handle. Incontrast, a liquid is one of the four fundamental states of matter.Independent laboratory tests and tests from a centrifuge maker haveconfirmed the feedstock processed by the methods disclosed herein isliquefied, or exists in a liquid state. A liquid is neither solid norgas and is characterized by free movement of the constituent moleculesamong themselves without a tendency to separate. Id.

The final step to producing a marketable product is to recover one ormore hydrocarbons from the liquidated feedstock material at process 170.Process 170 also may entail off gassing of methane and other gasses. Thehydrocarbons may be removed or separated in process 180 through the useof a fine me shed weir dam, by the use of chemical separation agents, orany number of other types of existing separation methods, including acentrifuge. The size of the centrifuge would vary depending on thevolume of liquid to be separated.

When the mixture was centrifuged at process 170, the lighter materials,such as the water and liquid hydrocarbon products were observed in theupper layer or layers. The heavier hydrocarbons, and any elements, andminerals that do not liquefy were observed at the bottom in strata ofvarious shades of brown. At the very bottom, almost black in appearance,were the heavier metals, such as gold and platinum. The composition ofthe recovered products depends directly on the composition of thefeedstock.

There are several different manufacturers of large commercial decantersand centrifuges on the market, such as from Flottweg SeparationTechnology of Vilbiburg, Germany. Some are vertical, and others arehorizontal. Such centrifuges come in many sizes and models. They canprocess any residual sludge in quantities from 60 gallons per minute(gpm) to 1,000 gpm.

The advantages of using a centrifuge to separate the various liquidhydrocarbon products and sludge is that while there is only one feedinlet, there can be multiple discharge outlets, and they can be used todecant or dewater the liquid hydrocarbon products from any incidentalsludge by gravity with variously meshed weir dams built into thecentrifuge body. The solid sludge is removed from the distal end and canthen be recovered using additional and existing ore separationtechnologies.

In another embodiment, components of the liquid hydrocarbon product areseparated by use of a meshed weir dam alone.

In another embodiment, components of the liquid hydrocarbon products areseparated by use of a centrifuge or a hydrocyclone.

In another embodiment, components of the liquid hydrocarbon product areseparated by use of one or more a filters.

In another embodiment, components of the liquid hydrocarbon product areseparated by use of chemical agents such as soap, salts, or any otherchemical agent normally used by a person of ordinary skill in the art.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an”, and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprise”and/or “comprising”, when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneof more other features, integers, steps, operations, elements,components, and/or groups thereof.

The corresponding structures, materials, acts, and equivalents of allmeans or step plus function elements in the claims below are intended toinclude any structure, material, or act for performing the function incombination with other claimed elements as specifically claimed. Thedescription of the present invention has been presented for purposes ofillustration and description, but is not intended to be exhaustive orlimited to the invention in the form disclosed. Many modifications andvariation will be apparent to those of ordinary skill in the art withoutdeparting from the scope and spirit of the invention. The embodiment waschosen and described in order to best explain the principles of theinvention and the practical application, and to enable others ofordinary skill in the art to understand the invention for variousembodiments with various modifications as are suited to the particularuse contemplated.

While the preferred embodiment to the invention has been described in anillustrative manner, it is to be understood that the terminology whichhas been used is intended to be in the nature of words of descriptionrather than words of limitation. Many modifications and variations ofthe invention are possible in light of the above teachings. Therefore,within the scope of the appended claims, the invention may be practicedother than as specifically described.

What is claimed is: 1) A biodigester for recovering one or morehydrocarbons from a feedstock, the feedstock including one or more ofoil shale, tar sand, coal and cellulose, the biodigester comprising: arotating mixing drum with an inside surface, an outside surface, and aradial opening at a first axial end; a drive ring at a second axial endconfigured to rotate the mixing drum about an axis in both a clockwiseand a counter clockwise; a removable lid configured to cover and rotatewith the radial opening, the removable lid comprising a elastomericgasket, wherein the elastomeric gasket is sandwiched between the radialopening and the removable lid; a rotating joint member attached to acenter of the removable lid; and a stationary lever arm attached to therotating joint member, the stationary lever arm configured to hold theremovable lid airtight against the radial opening. 2) The biodigester ofclaim 1, further comprising a pressure relief valve penetrating theremovable lid. 3) The biodigester of claim 1, further comprising amixing vane fixedly secured and extending from the inside surface of therotating mixing drum. 4) The biodigester of claim 3, wherein the mixingvane spirals from the first coaxial end to the second coaxial end. 5)The biodigester of claim 1, further comprising an elastomeric gasket,wherein the elastomeric gasket is sandwiched between the radial openingand the removable lid; and a first lever arm attached to the removablelid, the lever arm configured to hold the removable lid airtight againstthe radial opening. 6) A biodigester for recovering one or morehydrocarbons from a feedstock, the feedstock including one or more ofoil shale, tar sand, coal and cellulose, the biodigester comprising: arotating mixing drum with an inside surface, an outside surface, and aradial opening at a first axial end; a drive ring configured to rotatethe mixing drum about an axis in both a clockwise and a counterclockwise; a removable lid configured to cover and rotate with theradial opening, the removable lid comprising a elastomeric gasket,wherein the elastomeric gasket is sandwiched between the radial openingand the removable lid; and a first lever arm attached to the removablelid, the lever arm configured to hold the removable lid airtight againstthe radial opening. 7) The Biodigester of claim 6 further comprising: ahinge bar rigidly attached to the first lever arm and rotationalattached to a stationary frame; and a second lever arm fixedly attachedto the hinge bar. 8) The Biodigester of claim 7, wherein the framerotates with the mixing drum. 9) A biodigester for recovering one ormore hydrocarbons from a feedstock, the feedstock including one or moreof oil shale, tar sand, coal and cellulose, the biodigester comprising:a rotating mixing drum with an inside surface, an outside surface, and aradial opening having a center point and located at a first axial end; adrive ring configured to rotate the mixing drum in both a clockwise anda counter clockwise direct about a substantially horizontal axis thatextends through the center of the radial opening; a plurality of mixingvanes attached to the inside surface of the mixing drum configured topick up a portion of the feedstock and drop it from a height into thebottom as the portion is lifted to the height by the mixing vane. 10)The biodigester of claim 9, wherein the feedstock comprises fragmentedpebble sized oil shale and a biomedium. 11) The biodigester of claim 10,wherein a simultaneous biotic action of the biomedium and the droppingof the feedstock by the mixing vanes gradually reduces the pebble sizedfeedstock to a liquid state.